Researchers at the Maryland NanoCenter at the University of Maryland, College Park, have developed new systems for storing electrical energy derived from alternative sources that are, in some cases, 10 times more efficient than what is commercially available.

"Renewable energy sources like solar and wind provide time-varying, somewhat unpredictable energy supply, which must be captured and stored as electrical energy until demanded," says Gary Rubloff, director of the University of Maryland's NanoCenter. "Conventional devices to store and deliver electrical energy - batteries and capacitors - cannot achieve the needed combination of high energy density, high power and fast recharge that are essential for our energy future."

Researchers working with Rubloff and his collaborator, Sang Bok Lee, have developed a method to significantly enhance the performance of electrical energy storage devices.

Using new processes central to nanotechnology, researchers create millions of identical nanostructures with shapes tailored to transport energy as electrons rapidly to and from very large surface areas where they are stored. Materials behave according to physical laws of nature.

The Maryland research team's new devices are electrostatic nanocapacitors, which dramatically increase energy-storage density of such devices - by a factor of 10 over that of commercially available devices - without sacrificing the high power they traditionally characteristically offer, according to the Maryland NanoCenter.

This advance brings electrostatic devices to a performance level competitive with electrochemical capacitors and introduces a new player into the field of candidates for next-generation electrical energy storage.